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Question 1

What are the HPFW htrs extraction steam supplies

Answer 1

3rd stage ext.  - #7 HPFW and 1st stage heater 
5th stage ext.  - #6 HPFW
Cold Reheat    - #5 HPFW
1st htr drains    - #6 HPFW
2nd htr drains - #7 HPFW
MSR Drain tnk - HDT

Question 2

What are the HPFW htrs extraction steam supplies

Answer 2

3rd stage ext.  - #7 HPFW and 1st stage heater 
5th stage ext.  - #6 HPFW
Cold Reheat    - #5 HPFW
1st htr drains    - #6 HPFW
2nd htr drains - #7 HPFW
MSR Drain tnk - HDT

Question 3

What are the LPFW htrs extraction steam supplies

Answer 3

8th stage ext. - #4 LPFW
9th stage ext. - #3 LPFW
11th stage ext. - #2 LPFW
12th stage ext. - #1 LPFW

Question 4

Which FW htrs have BTV’s

Answer 4

• 7
• 6
• 5
• 4 (has 2 BTV’s)
• 3

Question 5

Which htrs have extraction steam Supply Block vlvs and what is their auto feature

Answer 5

• 6&7 Auto close on htr hi-hi level

- 5 Auto close on HDT hi-hi level

Question 6

Which htr does NOT have a drain vlv and why?

Answer 6

• 5A does not have an ext drain vlv

- Due to the short run of pipe

Question 7

What level in the MSR Drain tank will trip the main turbine

Answer 7

• -3”

- which is just below base of MSR

Question 8

How does the #5 HPFW htrs differ from the other HPFW

Answer 8

• It has no level control, it drains directly to HDT

- #5 press = HDT press.

Question 9

What regulates HDP flow

Answer 9

• HDT level controller

Question 10

How do HPFW Htrs react to a Hi-Hi level

Answer 10

• Closes extraction line isolation
• Closes BTV
• Closes upstream NLCV
• Opens MOV drain vlv
• 1st & 2nd RHDT’s vents swap to condenser
• # 5 HPFW htr has no level control

Question 11

How do LPFW Htrs respond to a Hi-Hi level

Answer 11

• Isolates htr string (CD)
• Isolates/ vents air to BTV
• Solenoid dump for Ext drain line dumps to fail open
  the drain line AOV

Question 12

How are the HPFW htrs vented

Answer 12

• HPFW vents combine together and vent to condenser

- Htr vent flow controlled by orifice at each htr

Question 13

How are LPFW Htrs vented

Answer 13

• LPFW htrs vent though orifice and to condenser

- Vents are individual vents

Question 14

How are the 1st and 2nd stage MSR htr drain tanks vented

Answer 14

• A & C Htr drain tanks vents combine together
• B & D htr drain tanks vents combine together
• Vent controlled by orifice at each htr
• A vent isolation vent to HPFW
• B vent isolation vents to Condenser

IF power lost to 2nd stage Reheater stop vlv & turb trip:

• BOTH 2nd stage htr drain vents CLOSE
• prevents flow path of MS to condenser
• prevents excessive RCS cooling

Question 15

How do the MSR htr drain tank vents fail

Answer 15

Loss of Power or Air

• A vlvs fail closed to HPFW
• B vlvs fail open to condenser

Question 16

What is used to cool the blowdown stack and what temperature is maintained

Answer 16

• DS
• 150*F
• Unit 2 only has manual vlv for cooling

Question 17

How does the MSR Drain tank NLCV operate

Answer 17

• AOV
• Fails Closed Loss of air
• control band 7”
• Auto Close on HDT Hi-Hi

Question 18

How does the MSR Drain Tank HLCV operate

Answer 18

• AOV
• Fails OPEN loss of air
• Failed OPEN until 10% turbine load

Question 19

How does the MSR 1st stage RDT NLCV operate

Answer 19

• AOV with solenoid air dump
• Fail CLOSED loss of air or power
• Auto CLOSE Hi-Hi in #6 HPFW htr

Question 20

How does the MSR 1st stage RDT HLCV operate

Answer 20

• AOV with solenoid air dump
• Fails CLOSED loss of air
• Loss of power still allows controller control
• Failed OPEN until 10% turbine load when in Auto

Controller controls when:

• Auto and >10% turbine load
• Steam Blanketing
• OPEN when in Purge

Question 21

How does the MSR 2nd stage RDT NLCV operate

Answer 21

• AOV
• Fails CLOSED loss of air or power

-Auto Close on Hi-Hi in #7 HPFW htr

Question 22

How does the MSR 2nd stage RDT HLCV operate

Answer 22

• AOV with Solenoid air dump
• Fails OPEN loss of air
• Loss of power still allows controller control

Controller controls when:

• Auto and >20% turbine load
• Steam Blanketing
• OPEN when in Purge

Question 23

What are the different modes for the Steam Blanketing Mode Selector Switch and how does it control MSR RDT control vlvs

Answer 23

• Auto, Purge, Steam Blanket

Auto:

• 1st/ 2nd stageHLCV’s failed open if < 10/20% turb load
• Modulate to maintain level

Purge:
- 1st/ 2nd stage HLCV’s OPEN

Steam Blanket:
- Both NLCV/HLCV maintain level

Question 24

How do 1st stage MSR RDT vent vlv operate if the associated Heater Steam Block Valve comes off open seat

Answer 24

IF in Auto:

• Vent to HPFW goes Closed
• Vent to Condenser Opens

Caused by HiHi auto closing Steam vlv or HS closing

Question 25

What are the different modes of the 1st/ 2nd Stage Scavenging Mode Selector Switch and how does it control MSR RDT Vent vlvs

Answer 25

- 2 separate switches which control each stage - Auto, Purge, Steam Blanket Auto: - Block vlv Full Open - opens vents to ED closes Cond. - Block vlv not full open - Vent Swap Purge: - Closes Vent to ED - Opens Vent to Condenser

Question 26

How do the 1st stage MSR RDT vents fail

Answer 26

Loss of Air or Power - vlv to ED Fails CLOSED - vlv to Condenser Fails OPEN

Question 27

how do the 2nd stage MSR RDT vents fail

Answer 27

Loss of Air or Power - vlv to ED Fails CLOSED - vlv to Condenser Fails OPEN

Question 28

What automatic feature is there for the 2nd Stage MSR RDT and what is it protecting

Answer 28

IF power is lost to 2nd Stage Reheater steam isolation AND a turbine trip occurs - Vent to Condenser will CLOSE - Prevents steam flow path to condenser - prevents excessive cooling of RCS

Question 29

What is indicated by DCA too low/ high and what is the concern with each condition

Answer 29

DCA High: - Water level too LOW - Fluid velocity too HIGH, damages tubes DCA Low: - Water level too HIGH - Reduced heat transfer due to covered tubes

Question 30

What is the purpose of the BTV's

Answer 30

- Prevents reverse steam flow on Turbine trip - Helps prevent Turbine Overspeed when unloaded - Prevents moisture carryover from hi-hi htr or HDT - Prevents Turbine Blade damage

Question 31

How are #7 HPFW BTV's different than the other BTV's

Answer 31

- They are located upstream of Steam block vlv | - Allows Htr isolation without isolating Extraction steam to MSR 1st stage htr

Question 32

What will cause the BTV to depressurize?

Answer 32

- Associated htr Hi-Hi - Associated LPFW string Hi-Hi - Turbine Trip

Question 33

How are the Extraction supply line drain vlvs different Between HPFW and LPFW

Answer 33

HPFW - MOV's - 1 for each line, except for 5A due to short pipe - NH LPFW: - AOV's - Fail OPEN on loss of air or power - 1 for each line on #3/4 htrs - NN

Question 34

How are the CR controls different for the HPFW and LPFW Extraction line drains

Answer 34

HPFW: - 3 position - Jog Open/Close LPFW: - 2 position - Open/Close

Question 35

What will Cause the HPFW extraction line drains to Open

Answer 35

- Feedwater htr hi-hi - Turbine trip - extraction steam block vlv HS to close - 5A does not have a drain line, short pipe

Question 36

What will Cause the LPFW extraction line drains to Open

Answer 36

- Heater string Hi-Hi | - Turbine Trip

Question 37

What level is the HDT Hi-Hi and what auto actions occur

Answer 37

``` 9 feet Isolates the following: - MSR Drain tank NLCV - #6 HPFW NLCV - #5 HPFW Extraction steam MOV - #5 HPFW BTV air ported ```

Question 38

What are the HDP Auto Trips

Answer 38

- Lo-Lo level 4ft - Lo-Lo Flow 711 gpm for 15 seconds - Electrical protection

Question 39

How does the HDT HLCV operate

Answer 39

- AOV | - Fails OPEN loss of air

Question 40

What are the HDP's power supplies

Answer 40

A - NBN-S02 B - NBN-S01 - Dont forget they are "backwards"

Question 41

When are we dictated to enter Single HDP operation

Answer 41

- If HDP will be out of service for > 1 hour

Question 42

How are the MSR's operated during Single HDP operation

Answer 42

- 2nd Stage htr valved out | - 1st stage MSR RDT NLCV failed CLOSED

Question 43

Describe the HDP START sequence

Answer 43

- HS to Start - Pump Starts - 5 second delay - Mini Flow opens - 2 minutes after start Disch vlv goes open -Minimizes starting current due to start at shutoff head

Question 44

How does the HDP Mini-flow operate

Answer 44

- AOV - Fails OPEN loss of air or power - Opens when <1600 gpm - Closes when >3200 gpm

Question 45

How does the HDT disch vlv operate

Answer 45

- AOV | - Fail CLOSED on Loss of Air or Power